(For instance, would you believe a “Deadpool” movie has been in the works for more than five years? Yeah, I was surprised by that one, too.)

“[Ryan Reynolds] is, I think, the only guy who can play that character. He is that character,” Katz told MTV. “I have to say it’s one of the proudest things I’ve done in my career and took me five extra years to do it, but to finally get him into that role and get it done is something I’m very proud of.”

According to Katz, Deadpool’s journey to the big screen (and Reynolds’ connection to the character), began around the time when plans were being hashed out for “Blade: Trinity,” the third installment of the film franchise based on Marvel Comics’ vampire hunter. The film was written and directed by David Goyer, and at the time, Katz was serving in a similar capacity for New Line Cinema and “Blade” as he later served for Fox on “Wolverine.”

“All the way back to Ryan, Goyer and I on ‘Blade: Trinity,’ we were trying to put together a deal at New Line for a ‘Deadpool’ movie,” said Katz. “We thought the rights were clear and not part of the ‘X-Men’ universe, so Ryan could play the character and Goyer could write. I can’t remember why — I think they wanted to do a ‘Blade’ spin-off instead — but it didn’t come together. But Ryan, to his credit, has remained obsessed with the character.”

As for the other fan-favorite character making his big-screen debut, Katz had nothing but praise for Kitsch’s performance as Gambit, another mutant of questionable morals who rose to prominence in the ’90s as one of the most popular X-Men.

“There’s no question that I think Gambit’s going to play well,” said Katz. “Put Taylor in a trenchcoat and give him a staff, and watch out. He’s a tough kid, and he did a lot of his own stuff — and he looked like a million bucks doing it.”

Much like Deadpool’s journey to theaters, Katz told MTV that the decision to bring Gambit into the mix was also subject to a lengthy debate. And like Deadpool, Gambit experienced a few starts and stops along the way, too.

“The discussion is always, ‘Is this a good use of this character or do we want to save them to fully use down the line?’ — and that was the Gambit debate in the original trilogy of movies,” explained Katz. “With the original trilogy, there was also the idea that he and Wolverine would have tried to fit the same space, and it would been awkward. They understood that Gambit was popular, but was it worth just popping him in as a throwaway character, and not in service of setting up something down the line? Now I think there is a level of strategy in how we grow these things, and what characters can transition between multiple films.”

“The unique challenge of the X-Men universe — and in my opinion the beauty of it — is the tapestry,” added Katz, . “These movies, particularly with some of the films they’re looking to be doing, they all touch and build this big weave that’s unlike any sort of franchise.”

“It’s about seeding them, and in some cases even just teasing them, so it keeps the audience between the two years between movies,” said Katz. “It’s no different than teasing Sam Jackson at the end of ‘Iron Man.’ It’s a very basic sort of psychological thing, but it works. If you can send your fans out of that movie excited to go back in for the next round, that’s half the battle.”